Penile porokeratosis mimicking annular lichen planus

Sir, Porokeratosis is a group of cutaneous diseases presented by epidermal keratinization [1]. Herein, we report the case of a patient with porokeratosis who responded well to carbon dioxide (CO2) laser therapy. A 22-year-old Vietnamese male visited our department with an asymptomatic plaque on the penis present for three months. He denied a family history of similar lesions. A cutaneous examination of the penis revealed an annular, well-circumscribed plaque with slightly raised borders with scales (Fig. 1a). Other mucocutaneous lesions were absent. Fungal microscopy, a rapid plasma reagin (RPR) test, and a Treponema pallidum hemagglutination (TPHA) test were negative. Histological findings revealed a hyperkeratotic lesion with a discrete parakeratotic column. There was the presence of a cornoid lamella, which was a parakeratotic column overlying a small vertical zone of dyskeratotic and vacuolated cells within the epidermis (Fig. 2a). There was also a focal loss of the granular layer. A mild lymphocytic infiltrate could be seen around an increased number of capillaries in the underlying dermis (Fig. 2b). CO2 laser removal was performed. There was no recurrence after a twelve-month follow-up (Fig. 1b). However, a hypopigmented scar was seen. Porokeratosis is an uncommon disorder of keratinization with clinical variants, such as classical porokeratosis of Mibelli, disseminated superficial actinic porokeratosis, linear porokeratosis, and porokeratosis palmaris et plantaris disseminata [2]. Porokeratosis involving the genital areas and other adjacent sites is rare [2]. Genital porokeratosis was first described by Helfman in 1985 [3]. More than 69 cases have been reported in the literature [1]. The pathophysiology of genital porokeratosis remains unknown. It has been supposed that porokeratosis is linked to repeated minor frictional trauma. A benign lesion may transform into squamous cell carcinoma or basal cell carcinoma [4]. However, no malignant transformation of genital porokeratosis has been noted in the literature. Genital porokeratosis manifests itself clinically as classic or plaque-type porokeratosis of Mibelli [2]. Histological findings revealed a cornoid lamella with the absence of a granular layer and dyskeratotic cells in the upper spinous zone [2]. Our case may mimic some annular lesions, such as secondary syphilis, fungal infection, and annular lichen planus. Because a fungal examination and syphilis serology were negative, we could exclude fungal infection and annular secondary syphilis. The distinctive histology of porokeratosis such as a cornoid lamella with a decreased granular layer may help to differentiate between porokeratosis and annular lichen planus [4]. Numerous therapeutic methods of treatment exist, including surgical excision, CO2 laser, cryotherapy, topical retinoids, 5% 5-fluorouracil, vitamin D3 analogs, imiquimod cream, and 3% diclofenac gel [2,5].

Porokeratosis: An enigma beginning to unravel

Porokeratosis is a keratinization disorder with unclear etiopathogenesis, varied clinical presentation and characteristic histopathology, and is usually unresponsive to current therapeutic options. Until now, it was considered to be a clonal disorder with immunity, ultra violet radiation and other factors playing important roles in etiopathogenesis. It is now known that abnormalities in the mevalonate pathway are responsible for this clonal keratinization abnormality. New variants of porokeratosis like eruptive bullous, pruriginous, lichen planus like, follicular variants and porokeratoma have been described. While the cornoid lamella is the classical histopathologic feature, dermoscopy and reflectance confocal microscopy make the diagnosis clearer. Development of malignancy in a few variants is a concern. Linear, disseminated superficial actinic and giant lesions are most prone to developing malignancies. Bowen’s disease, squamous cell carcinoma, basal cell carcinoma and even melanoma have been reported in cases of long-standing porokeratosis. Newer modalities of therapy such as photodynamic therapy, ingenol mebutate and HMGCoA inhibitors may play a role in the future.

A rare case of genital porokeratosis clinically misdiagnosed as lichen planus

Introduction/Objective Porokeratosis is a clonal disorder of keratinization characterized by atrophic patches surrounded by a histologically distinctive hyperkeratotic ridge-like border called the cornoid lamella. Porokeratosis occurring on the genital area is considered a rare entity and much more unusual when in isolated form Methods/Case Report This is a case of a 54-year old man who presented with a penile lesion that has been present for 10 years, unchanged, non-bleeding and non-pruritic. There was no history of genital ulcer or inguinal swelling, neither any history of sexual promiscuity. The patient has a history of basal cell carcinoma on the right nasal area managed with Mohs surgery and scalp actinic keratoses treated with liquid nitrogen. On examination, there was a solitary 6-mm red linear macule with collarette of white scale on the corona of the penis. There was no similar lesion seen on other body parts. His blood investigations, including venereal disease research laboratory test (VDRL) and HIV screening, were negative. The initial clinical diagnosis was lichen planus, and triamcinolone was administered for three months with minimal benefit. This failed steroid management prompted a shave biopsy Results (if a Case Study enter NA) Histologic sections showed a column of hyperkeratosis arising from the epidermis (cornoid lamella) with absent granular layer and dyskeratotic cells beneath the cornoid lamella, confirming the diagnosis of porokeratosis limited to the genitalia Conclusion Porokeratosis is considered a pre-malignant condition based on clonal proliferation, dyskeratotic cells, abnormal keratinocyte maturation and p53 overexpression. Malignant progression to Bowen’s disease and squamous cell carcinoma has been documented in 6.9 to 30% of cases.

Coexist of Disseminated Superficial Actinic Porokeratosis and Porokeratosis Ptychotropica with A Novel MVK Gene Mutation: A Case Report and Literature Review

Background: Porokeratosis is a rare, acquired or inherited disorder of keratinization. There are numerous clinical types of porokeratosis and they could coexist in one patient and in multiple members of an affected family. However, coexist of disseminated superficial actinic porokeratosis (DSAP) and porokeratosis ptychotropica (Ppt) is rare.Case presentation: A 45-year-old man presented with long-standing skin lesions. Physical examinations found numerous small, brown 2- to 4-mm patches on his face and several hyperkeratotic, verrucous plaques on his trunk and extremities. His father and one of his brothers also had similar lesions for years. Skin biopsies showed a cornoid lamella in the epidermis. And we identified c.155 G>A mutation of the mevalonate kinase (MVK) gene convertting a serine residue to asparagine (p.Ser52Asn) was the causative mutation for porokeratosis in this family. The clinicopathologic diagnosis of DSAP and Ppt with a novel MVK gene mutation was made. The hyperkeratotic plaques on the patient's scrotum were completely removed by microwave knife for more than 10 times. Conclusion: We report an unusual case of DSAP coexisting with Ppt and identified a novel MVK gene mutation in this patient's family. The microwave knife is an effective and safe therapy for porokeratosis.

A RARE CASE OF GENITAL POROKERATOSIS

Porokeratosis is a keratinization disorder of unknownetiology. It is characterized by well defined annular plaques with central scarring or pigmentation and raised keratotic border. Disseminated superficial actinic porokeratosis, linear porokeratosis, porokeratosispalmaris et plantaris ,punctateporokeratosis are different clinical variants. Keratotic border is microscopically characterized by a column of parakeratotic cells invaginating the epidermis known as cornoid lamella which is a characteristic finding. Porokeratosis localized to the genital region is very rare. These lesions are mostly asymptomatic but there can be occasional pruritus. It mostly occurs on the scrotum followed by penis however adjoining areas like thighs, buttocks, natal cleft can also be involved. There are very few reports in Indian literature of porokeratsis limited to the genital region.

Squamous Cell Carcinoma Arising from Linear Porokeratosis - a case report and review of the literature

Porokeratosis belongs to a group of disorders of keratinization that are characterized by the histopathological feature of the cornoid lamella, a column of tightly fitted parakeratotic cells. The etiology of porokeratosis is still unclear. Different variants of porokeratosis (PK) have been subsequently recognized, each with its own specific properties in terms of morphology, distribution and clinical course. Linear porokeratosis is one of the variants of porokeratosis, a rare disorder of keratinization that may develop into several epidermal malignancies, squamous cell carcinoma being the most frequent among all of them. Thus, a clinical surveillance for malignancy is an imperative. We present a case of a 54-year-old man with non-healing ulcer of the lower leg caused by squamous cell carcinoma arising on long-standing linear porokeratosis. The treatment included wide excision of tumor with the reconstruction of the area. Acitretin was prescribed for linear porokeratosis treatment. The follow-up of our patient so far has shown that he does not have new malignant lesions after surgical excision.

Clinical and Dermoscopic Features of Pigmented Disseminated Superficial Actinic Porokeratosis: Case Report and Literature Review

Introduction: Porokeratosis is a benign hyperkeratotic skin tumour due to a clonal proliferation of keratinocytes and is characterised by a telltale annular threadlike configuration along the border of a skin-colored to erythematous papule that can expand centrifugally. Case Presentation: We are presenting a clinical and dermoscopic case of pigmented disseminated superficial actinic porokeratosis (DSAP) limited to the upper trunk of a white man with sun-damaged skin. Literature Review and Conclusion: A thorough review of PubMed failed to identify any previous reports on the dermoscopic appearance of pigmented porokeratosis. On dermoscopy, the presence of black dots limited to the periphery of the lesions is due to pigment incontinence and melanophages within the superficial papillary dermis limited to the area below the cornoid lamella. Pigmented DSAP is a unique morphological presentation of porokeratosis, and it is essential to be familiar with its clinical and dermoscopic presentation.

Unilateral Linear Punctate Palmoplantar Keratoderma: A Case Report

Punctate palmoplantar keratoderma (PPPK) is a rare entity with an estimated prevalence rate of 1.17/100,000. PPPK usually presents with bilateral asymptomatic, tiny, hyperkeratotic punctate papules and plaques on the palmoplantar surface. Among the PPPK varieties, the linear presentation is much rarer, and so far there have been only 3 case reports. Here, we report the case of a 27-year-old female Thai patient who presented to our outpatient clinic with unilateral asymptomatic linear thickening lesions on her right sole since childhood. There were no similar lesions on other parts of the body. A histopathologic examination revealed epidermal hyperplasia and hyperkeratosis without columns of parakeratosis or cornoid lamella. The other examinations were normal. The clinical and histological contexts were consistent with a diagnosis of unilateral linear PPPK. The patient was treated with topical 10% urea cream and 10% salicylic acid cream twice daily. To the best of our knowledge, this is the first reported case of unilateral linear PPPK in Thailand, and the fourth reported case worldwide.